Robert Nola and Howard Sankey provide an authoritative and comprehensive examination of the major theories of scientific method and the demarcation of science of the past fifty years. Beginning with the question of what methodology might mean, the authors explore the distinction between discovery and justification, and the ideas of values, rules, and principles. Informed by the latest thinking, the book offers students an excellent introduction to the idea of scientific method and a wide- ranging discussion of how philosophers and scientists have grappled with the question over recent years.